Topic: battery not enough power to run starter?

[jpbova]

My battery doesn't seem to have enough juice to run my electric starter.  I took the battery out of my 76' cb550 and tested it at autozone.  Everything was good.  We even put the battery on the charger still no luck starting it with the electric starter.  I recently redid all the wiring on the bike and all the relays seem good, so I'm stumped, an I'm wondering what else it could be?  It would be nice to have the electric starter because the bike his hard to start when cold with the kick starter.

*edit* the starter cranks the engine but not with enough juice to get it running and it usually stops cranking after 5 seconds

[Gordon]

Could be lots of things.  The solenoid could be going bad, the starter motor could be getting worn out, or the battery could be bad in spite of what the guy at Autozone told you. 

Jump the terminals on top of the solenoid with a screwdriver to see if the starter turns faster than it does by just pushing the button.  If the battery is good and the starter turns faster this way then your solenoid is the problem, but you have to be absolutely sure that the battery is in good condition before you can really start troubleshooting. 

[dhinch279]

Also be sure that the battery that you pulled from the 550 has enough amps to turn over whatever size engine you are trying to start. I don't know what size engine you are attempting to start but just a heads up, cuz it has happened to me.

[TwoTired]

Measure the battery voltage before and during and after the starter operation.
The starter can draw 120 amps during operation.  If the starter is drawing more than that, the battery voltage will drop below 9V and deplete quicker.  (A weak battery can also do this, however.)
Knowing this voltage, can also tell you if there is enough voltage to spark the coils.

If the solenoid is limiting current to the starter, bridging the posts will circumvent that problem.

Of course, the best test would be to measure the starter current draw during operation.  But, having a 200 or 300 amp meter for personal use is unusual.

A proper battery test will also test it under starting load.  Did Autozone do that test?

[jpbova]

no they didn't do the test under load!

I bridged the solenoid and it seemed to have the same result.  It seemed to turn with ever slightly more vigor, but the starter would only turn for 5 seconds then completely stop.  I'm going to pick up a new battery for it when I get new spark plugs.  could the coils be bad?

[BVCB650]

They may be, who knows, but that isn't what is keeping your starter from turning.

[TwoTired]

They may be, who knows, but that isn't what is keeping your starter from turning.

+1
However, if you have lower than 5 ohm coils, they will certainly draw more power during start operation.

[BVCB650]

Yes, correct. I can only assume it is a stock component but who the heck knoes after 30+ years. I found a wheat straw stock behind my sprocket cover, and as far as I know, there isn't any wheat within 300 miles of me. Had red clay too, when leads me to believe this bike was once in Oklahoma.

[TwoTired]

There is red soil in Arizona, too.

Saw it first hand a couple weeks ago in Sedona.  Heavy rains and a wash out.  Just washed it off the car a few days ago.

[KeithB]

"could be a lot of things..."
Start by getting a new battery.
Unless you get batteries tested by commercial/industrial retailers, it's unlikely that it has been load tested.
I don't trust auto parts retailers to properly test batteries.
In the meantime, jump from a car battery to get the bike started.
Do not have the car engine running.

[BVCB650]

There is red soil in Arizona, too.

Saw it first hand a couple weeks ago in Se dona.  Heavy rains and a wash out.  Just washed it off the car a few days ago.

Apparently, the chain broke at some time, and the little guard on the case was gone, allowing material to sling all over the oil switch and such. It was heavy hard pan clay. Took a chisel to get it off.